#!/bin/sh

set -e

#*************************************************************************
#*************************************************************************
OSMOSIS_BIN=osmosis
OSM2PGSQL_BIN=osm2pgsql
OSM2PGSQL_OPTIONS=
#OSM2PGSQL_OPTIONS="--flat-nodes /path/to/flatnodes --hstore"

BASE_DIR=/var/lib/mod_tile
LOG_DIR=/var/log/tiles/
WORKOSM_DIR=$BASE_DIR/.osmosis

LOCK_FILE=/tmp/openstreetmap-update-expire-lock.txt
CHANGE_FILE=$BASE_DIR/changes.osc.gz
EXPIRY_FILE=$BASE_DIR/dirty_tiles
STOP_FILE=$BASE_DIR/stop.txt

OSMOSISLOG=$LOG_DIR/osmosis.log
PGSQLLOG=$LOG_DIR/osm2pgsql.log
EXPIRYLOG=$LOG_DIR/expiry.log
RUNLOG=$LOG_DIR/run.log

EXPIRY_MINZOOM=10
EXPIRY_MAXZOOM=18

#*************************************************************************
#*************************************************************************

m_info()
{
        echo "[`date +"%Y-%m-%d %H:%M:%S"`] $$ $1" >> "$RUNLOG"
}

m_error()
{
    echo "[`date +"%Y-%m-%d %H:%M:%S"`] $$ [error] $1" >> "$RUNLOG"
    
    m_info "resetting state"
    /bin/cp $WORKOSM_DIR/last.state.txt $WORKOSM_DIR/state.txt || true
    
    rm "$CHANGE_FILE" || true
    rm "$EXPIRY_FILE.$$" || true
    rm "$LOCK_FILE"
    exit
}

m_ok()
{
    echo "[`date +"%Y-%m-%d %H:%M:%S"`] $$ $1" >> "$RUNLOG"
}

getlock()
{
    if [ -s $1 ]; then
        if [ "$(ps -p `cat $1` | wc -l)" -gt 1 ]; then
            return 1 #false
        fi
    fi
    
    echo $$ >"$1"
    return 0 #true
}

freelock()
{
    rm "$1"
    rm "$CHANGE_FILE"
}


if [ $# -eq 1 ] ; then
    m_info "Initialising Osmosis replication system to $1"
    mkdir $WORKOSM_DIR
    $OSMOSIS_BIN --read-replication-interval-init workingDirectory=$WORKOSM_DIR 1>&2 2> "$OSMOSISLOG"
    wget "http://osm.personalwerk.de/replicate-sequences/?"$1"T00:00:00Z" -O $WORKOSM_DIR/state.txt
else
# make sure the lockfile is removed when we exit and then claim it

    if ! getlock "$LOCK_FILE"; then
        m_info "pid `cat $LOCK_FILE` still running"
        exit 3
    fi

    if [ -e $STOP_FILE ]; then
        m_info "stopped"
        exit 2
    fi

    seq=`cat $WORKOSM_DIR/state.txt | grep sequenceNumber | cut -d= -f2`

    m_ok "start import from seq-nr $seq, replag is `osmosis-db_replag -h`"

    /bin/cp $WORKOSM_DIR/state.txt $WORKOSM_DIR/last.state.txt
    m_ok "downloading diff"
    
    if ! $OSMOSIS_BIN --read-replication-interval workingDirectory=$WORKOSM_DIR --simplify-change --write-xml-change $CHANGE_FILE 1>&2 2> "$OSMOSISLOG"; then
        m_error "Osmosis error"
    fi
    
    m_ok "importing diff"
    EXPIRY_METAZOOM=`expr $EXPIRY_MAXZOOM - 3`
    if ! $OSM2PGSQL_BIN -a --slim -e$EXPIRY_METAZOOM:$EXPIRY_METAZOOM $OSM2PGSQL_OPTIONS -o "$EXPIRY_FILE.$$" $CHANGE_FILE 1>&2 2> "$PGSQLLOG"; then
        m_error "osm2pgsql error"
    fi

    freelock "$LOCK_FILE"

    m_ok "expiring tiles"
    if ! render_expired --min-zoom=$EXPIRY_MINZOOM --max-zoom=$EXPIRY_MAXZOOM --touch-from=$EXPIRY_MINZOOM -s /var/run/renderd.sock < "$EXPIRY_FILE.$$" 2>&1 | tail -8 >> "$EXPIRYLOG"; then
        m_info "Expiry failed"
    fi

    rm "$EXPIRY_FILE.$$"
    
    m_ok "Done with import"
    

    

fi